\begin{tikzpicture}
    \pgfmathsetmacro{\R}{1.5}
    \tkzDefPoints{0/0/O}
    \tkzDefPoint(90:\R){A}
    \tkzDefRegPolygon[center,sides=5,name=P](O,A)
    \foreach \P [count=\i from 2] in {E,D,...,B} {
        \coordinate (\P) at (P\i);
    }

    \tkzDrawCircle[very thick](O,A)
    \tkzDrawPolygon[red, thick](A,C,E,B,D)

    \tkzDefPoint(270:\R){Z}
    \tkzLabelPoints[white,below](Z)
\end{tikzpicture}

